package com.common.util;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Random;

public class Randoms {
	private static final Random RANDOM = new Random();
    //定义验证码字符.去除了O和I等容易混淆的字母
    public static final char ALPHA[]={'A','B','C','D','E','F','G','H','G','K','M','N','P','Q','R','S','T','U','V','W','X','Y','Z'
            ,'a','b','c','d','e','f','g','h','i','j','k','m','n','p','q','r','s','t','u','v','w','x','y','z','2','3','4','5','6','7','8','9'};
 
    /**
     * 产生两个数之间的随机数
     * @param min 小数
     * @param max 比min大的数
     * @return int 随机数字
     */
    public static int num(int min, int max)
    {
        return min + RANDOM.nextInt(max - min);
    }
 
    /**
     * 产生0--num的随机数,不包括num
     * @param num 数字
     * @return int 随机数字
     */
    public static int num(int num)
    {
        return RANDOM.nextInt(num);
    }
 
    public static char alpha()
    {
        return ALPHA[num(0, ALPHA.length)];
    }
    
    /**
     * 生产主键id
    * @Title: createId
    * @Description: 生产yyyyMMddHHmmss加两位随机数
    * @param @return    
    * @return String    
    * @throws
     */
    public static String createId(){
    	String num = String.valueOf(new Random().nextInt(90)+10);
    	SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
    	String date=sdf.format(new Date());
    	return date+num;
    }
}